Colorado Altitude Pressure Compensation?

co1simba · Post by **co1simba** » Mon Feb 02, 2009 1:27 am

Hey guys, I live in Colorado and have a few questions. Atmospheric pressure here is about 830-850 mBar compared to sea level of 1000... (duh) What I'm having trouble with is at key-on engine-off the MAP sensor reads -5 inHg whereas my boost gauge will read 0. So eCtune is reading different from my gauge and I know that eCtune is wrong. Should I rescale eCtune by setting sea level to 840 mBar? How will this effect everything when I go to boost? Thanks, co1simba

Post by **calvin** » Mon Feb 02, 2009 8:49 am

your boost gauge is wrong. Boost gauge does not work with baro. eCtune is correct. -5 HG isnt that arround 850mbar? set mbar in eCtune setting 850 or read from baro sensor

elevation · Post by **elevation** » Mon Feb 02, 2009 12:00 pm

everything is 3psi off. Its no big deal. just tune the columns proper, leave the sea leavel pressure where it is cause if you go down in elevation youll start gaining atmophere psi.

Post by **calvin** » Mon Feb 02, 2009 12:29 pm

mbar sealevel. you can read from BARO it will only change in ectune display values. because in rom everything is based on hex values

elevation · Post by **elevation** » Mon Feb 02, 2009 12:55 pm

I always read from baro.

co1simba · Post by **co1simba** » Tue Feb 03, 2009 12:07 am

Ok, so when i go into boost having set my wastegate at 7 psi, the boost gauge will read 3-4psi and ectune will read 7psi? So will i be boosting an additional 5psi to bring it out of vacuum (according to eCtune) and then 7psi to the peak for a total of 12psi? Im still a little lost. Why wouldn't the boost gauge read -xx inHg if it is calibrated to 0 at sea level? -co1simba

Post by **calvin** » Tue Feb 03, 2009 2:07 am

boost gauge assume sea level is 1013mbar or so mbar. If you put the proper sea level in ectune you will have the actual correct value in ectune. not sure how the wg spring and psi will react